A Cambodian-American filmmaker named Kalyanee Mam spent several years making a movie in Cambodia. The movie is a documentary called “A River Changes Course.” It tells the story of three young people, and how life is changing for them. One of the young people is Sari Math. When the documentary begins, Sari is 14-years- old and fishing with his father.

Kalyanee Mam describes the scene.

“You can see the hands, you can see the nets, and you can feel the waves, you know, crashing against the boat.”

Sari Math and his family live on a floating village in the middle of a river. The river is very unusual. Every year it changes direction. During the rainy season it flows one way. During the dry season it flows the other way.

“I found it’s the perfect metaphor for what is happening in Cambodia right now. You know, all the changes that are happening, and all the development that’s taking place. There’s a bit of uncertainty—actually not a bit, but a lot of uncertainty for people right now in Cambodia about what’s going to happen to them and what course their lives will take.”

For Sari Math’s family in Cambodia, development means more people are fishing in the waters near their village. Some use large traps or dynamite to catch more fish. As a result, the fish are disappearing — and so is the income for Sari Math’s family.

“They are Cham Muslim, they speak a very distinct language, they have a very distinct culture, and it’s a very distinct religion. And, you know, without their source of livelihood which is fishing, you know their life could change, you know, dramatically, and it is changing dramatically.”

By the end of the film, Sari Math is 16. He has had to quit school. And he has left his floating village. Even though he is trained as a fisherman, he is looking for a job on a cassava farm.

Kimseng Men is a reporter for VOA’s Khmer service. He says historically in Cambodia, most people lived in villages with their families. They earned money from farming, fishing and the forest. But these days things are different.

“You wake up one day, you see the sound of a bulldozer coming to bulldoze your forest, your plantation.”

He says people in this position often sell their land. In some cases this is because their neighbors have already sold their land to a developer. In other cases people do not even have a choice.

“For example, some people live in the area for ten, twenty years, and then one day the court would say, you’re illegal because you have no paperwork. And the new owner coming in, they have proper legal paper. And they are the rightful owner. So things like this happen.”

Kimseng Men says it is also increasingly common in Cambodia for people to move away from their families. He says some move to cities to find new jobs. Others borrow money to keep their land. Then they have to work in other areas to repay their debt.

But he says some people are doing quite well in Cambodia.

“Those who are in power, the elite team, those who are very well connected to the leader are the ones who benefit the most.”

These include officials who are in a position to help foreign investors, he says.

“I said, your country, Cambodia, has very good laws. But the problem is, who’s implementing it. Who’s in charge of it? And if those who implement the law put it in a way to serve their own group interest, and then you’re not protecting the people anymore.”

Kimseng Men says ordinary people also have a responsibility. They can find out what changes are happening in their area. They can join with their neighbors and tell the government how they want to manage those changes, he says.

“They should let them know in advance. They should not wait until it’s too late. When they already agree to those investments and then come in with their machinery, it’s hard to pull them away.”

Filmmaker Kalyanee Mam agrees that development can be positive.

“I think that change is inevitable. Changes are, you know, to a certain extent, you know, good for you.”

She says changes such as migration away from rural areas are allowing more women to find work and provide for their families. But migration is also taking resources from those rural areas. And developers who harvest large amounts of fish or trees are affecting the country’s natural resources.

“You know the changes are, in a way they’re helping people because they’re giving them opportunities, but at the same time they’re not cognizant of the impact that it’s having on people’s lives.”

Kalyanee Mam says these impacts are the reason she made her film. She says she wanted to show the beauty of Cambodians’ daily life. That life will be lost, she says, if people are not more aware of the effects of globalization.

Kalyanee Mam’s film, “A River Changes Course,” won the world cinema prize for documentary at the Sundance Film Festival this year. It is also playing at the Environmental Film Festival in Washington, DC.

Flo Stone founded the DC Environmental Film Festival in 1993. It lasts 13 days and is showing 190 films from 50 countries this year.

“We have films this year about the Amazon, about the Ganges, the Mississippi in America, the Rhine, a whole series of films on the Rhine winding through Europe, and other rivers in Africa and Asia.”

Ms. Stone says film is a powerful way to get people talking about the importance of rivers and other environmental issues.

In fact, one film, called “Revolution,” is all about activists for the environment.

Filmmaker Rob Stewart says a good many of them are under 25.

“We’ve got, you know, we’ve got kids on our side. And they’re the most powerful, most active, most energetic group on the planet, and it’s their future that’s at stake. So I think, for sure, I’m hopeful.”

A few years ago, Mr. Stewart made a movie about saving sharks. But now he says it’s not just sharks we need to save. It’s us.

That’s it for today. Thanks for listening to As It Is. Tell us what you want to hear about. And remember, you can listen to VOA news at the beginning of every hour Universal Time.